Testing NodeJS with Mocha: 'Require is not defined' - node.js

Question

EDIT:
As per the comment on the answer below: removing "type": "module" from package.json, which as I understand it is what makes Node understand 'import' and 'export' statements, and reverting everything to 'require' and 'module.exports' solved the issue.
Is there a way to keep 'import' and 'export' and still make Mocha work?
I have a very simple Node file that I'm trying to test with Mocha/Chai. The actual code is trivial, this is just to learn a bit about Mocha and how to use it. But when I run the Mocha test, I get the error ERROR: ReferenceError: require is not defined
`
I did some googling for people experiencing the same problem but the examples that I came up with were when they were running the test in the browser (see, for example, Mocha, "require is not defined" when test in browser).
The file I want to test, index.js
const argv = require('minimist')(process.argv.slice(2));
const digitTester = /\d/g;
const capTester = /[A-Z]/g;
const dict = {
length:10,
must_have_numbers: true,
must_have_caps: true
}
export default function passwordCheck(password) {
if (!password) return false;
if (typeof password !== "string") return false;
if (password.length < dict.length) return false; // assumes that 10 is a MINIMUM length
if (dict.must_have_numbers && !digitTester.test(password)) return false;
return !(dict.must_have_caps && !capTester.test(password));
}
if (argv._.length) {
console.log(passwordCheck(argv._[0]))
}
/**
* alternate version to check a lot of passwords:
*
* if (argv._.length) {
* for (const pwd of argv_) console.log(passwordCheck(pwd)
*}
*
*/
the mocha file, test/index.test.js
const chai = require('chai')
const expect = chai.expect
const passwordCheck = require('../index.js')
const tooShort = "A2a"
const noCaps = "a2abcdefghijklmnop"
const noNumber = "Aabcdefghijklmnop"
const good = "A2abcdefghijklmnop"
describe('password checking', () => {
it('should return false for passwords less than length 10', () => {
expect(passwordCheck(tooShort)).to.be.false;
});
it('should return false for passwords without a capital letter', () => {
expect(passwordCheck(noCaps)).to.be.false;
});
it('should return false for passwords without a number', () => {
expect(passwordCheck(noNumber)).to.be.false;
});
it('should return true for passwords that match criteria', () => {
expect(passwordCheck(good)).to.be.true;
});
});
and package.json
{
"name": "codetest",
"version": "1.0.0",
"main": "index.js",
"type": "module",
"scripts": {
"test": "mocha"
},
"keywords": [],
"author": "",
"license": "ISC",
"description": "",
"dependencies": {
"#types/minimist": "^1.2.1",
"#types/node": "^14.14.20",
"chai": "^4.2.0",
"minimist": "^1.2.5",
"mocha": "^8.2.1"
}
}
and the error message is
✖ ERROR: ReferenceError: require is not defined
at file:///Users/r/Documents/Projects/sandbox/pwd_checker/index.js:2:14
at ModuleJob.run (node:internal/modules/esm/module_job:152:23)
at async Loader.import (node:internal/modules/esm/loader:166:24)
at async exports.handleRequires (/Users/r/Documents/Projects/sandbox/pwd_checker/node_modules/mocha/lib/cli/run-helpers.js:94:28)
at async /Users/r/Documents/Projects/sandbox/pwd_checker/node_modules/mocha/lib/cli/run.js:341:25
error Command failed with exit code 1.
info Visit https://yarnpkg.com/en/docs/cli/run for documentation about this command.
Node 15.

Answer 1

Remove this line - "type": "module" from package.json and check whether it’s working or not.

Answer 2

Prepend your tests with the following:
import { createRequire } from 'module';
const require = createRequire(import.meta.url);
This is because you cannot require from an ESM module; for more info please see this comment on a nodejs issue.
Documentation: https://nodejs.org/api/esm.html#differences-between-es-modules-and-commonjs